Introduction to the special section on the neural substrate of analogical reasoning and metaphor comprehension

The special section on the neural substrate of relational reasoning includes 4 articles that address the processes and brain regions involved in analogical reasoning (Green, Kraemer, Fugelsang, Gray, & Dunbar, 2011; Maguire, McClelland, Donovan, Tillman, & Krawczyk, 2011) and in metaphor comprehension (Chettih, Durgin, & Grodner, 2011; Prat, Mason, & Just, 2011). We see this work as an example of how neuroscience approaches to cognition can lead to increased understanding of cognitive processes. In this brief introduction, we first situate the 4 articles in the context of prior cognitive neuroscience work on relational reasoning. We then highlight the main issues explored in these articles: different sources of complexity and difficulty in relational processing, potential differences between the roles of the 2 hemispheres, and the impact of individual differences in various cognitive abilities. The 4 articles illustrate a range of methodologies, including functional magnetic resonance imaging (fMRI; Green et al., 2011; Prat et al., 2011), event-related potentials (ERPs; Maguire et al., 2011), and different types of semantic priming (Chettih et al., 2011; Prat et al., 2011). They highlight the connections between research on analogy and on metaphor comprehension and suggest, collectively, that a cognitive neuroscience approach to relational reasoning can lead to converging conclusions.     

Processing of metaphoric language: An investigation of the three-stage model of metaphor comprehension

Recent experiments that have compared processing of metaphoric and literal language in light of the three-stage model have methodological weaknesses. The study reported in this paper was designed to circumvent these weaknesses. Findings of this study demonstrated longer reading times for metaphors when compared to literals. This result lends support to the three-stage model and to the possibility that serial processing occurs during metaphor comprehension.We would like to thank Dr. Andrew Ortony for kindly providing us with the paragraphs used as stimulus materials in this study. We would also like to thank Dr. Herbert Roitblat for his many helpful comments on earlier versions of this paper.     

ERP and behavioral evidence of individual differences in metaphor comprehension

In two experiments, we examined individual differences in metaphor processing. In Experiment 1, the subjects judged the literal truth of literal, metaphorical, and scrambled sentences. Overall, metaphors were more difficult to judge as false, in comparison with scrambled controls, suggesting that the metaphorical meaning was being processed automatically. However, there were individual differences in that high-IQ subjects showed more interference. These effects were reflected in ERP amplitude differences at the onset of N400 and after the response. In Experiment 2, the subjects completed IQ tests and a series of working memory tests and then rated and interpreted the same set of metaphors. The results showed that IQ was correlated with working memory capacity and that low-IQ subjects had similar ratings but poorer quality interpretations than did high-IQ subjects. The results were most consistent with a constraint satisfaction approach to metaphor comprehension.     

An fMRI investigation on image generation in different sensory modalities: The influence of vividness

In the present fMRI study the issue of the specific cortices activation during imagery generation in different sensory modalities is addressed. In particular, we tested whether the vividness variability of imagery was reflected in the BOLD signal within specific sensory cortices. Subjects were asked to generate a mental image for each auditory presented sentence. Each imagery modality was contrasted with an abstract sentence condition. In addition, subjects were asked to fill the Italian version of the Questionnaire Upon Mental Imagery (QMI) prior to each neuroimaging session. In general, greater involvement of sensory specific cortices in high-vivid versus low-vivid subjects was found for visual (occipital), gustatory (anterior insula), kinaesthetic (pre-motor), and tactile and for somatic (post-central parietal) imagery modalities. These results support the hypothesis that vividness is related to image format: high-vivid subjects would create more analogical representations relying on the same specific neural substrates active during perception with respect to low-vivid subjects. Results are also discussed according to the simulation perspective.     

Auditory language comprehension: an event-related fMRI study on the processing of syntactic and lexical information

The functional specificity of different brain areas recruited in auditory language processing was investigated by means of event-related functional magnetic resonance imaging (fMRI) while subjects listened to speech input varying in the presence or absence of semantic and syntactic information. There were two sentence conditions containing syntactic structure, i.e., normal speech (consisting of function and content words), syntactic speech (consisting of function words and pseudowords), and two word-list conditions, i.e., real words and pseudowords. The processing of auditory language, in general, correlates with significant activation in the primary auditory cortices and in adjacent compartments of the superior temporal gyrus bilaterally. Processing of normal speech appeared to have a special status, as no frontal activation was observed in this case but was seen in the three other conditions. This difference may point toward a certain automaticity of the linguistic processes used during normal speech comprehension. When considering the three other conditions, we found that these were correlated with activation in both left and right frontal cortices. An increase of activation in the planum polare bilaterally and in the deep portion of the left frontal operculum was found exclusively when syntactic processes were in focus. Thus, the present data may be taken to suggest an involvement of the left frontal and bilateral temporal cortex when processing syntactic information during comprehension.     

Auditory language comprehension: an event-related fMRI study on the processing of syntactic and lexical information

The functional specificity of different brain regions recruited in auditory language processing was investigated by means of event-related functional magnetic resonance imaging (fMRI) while subjects listened to speech input varying in the presence or absence of semantic and syntactic information. There were two sentence conditions containing syntactic structure, i.e., normal speech (consisting of function and content words), syntactic speech (consisting of function words and pseudowords), and two word-list conditions, i.e., real words and pseudowords. The processing of auditory language, in general, correlates with significant activation in the primary auditory cortices and in adjacent compartments of the superior temporal gyrus bilaterally. Processing of normal speech appeared to have a special status, as no frontal activation was observed in this case but was seen in the other three conditions. This difference may point toward a certain automaticity of the linguistic processes used during normal speech comprehension. When considering the three other conditions, we found that these were correlated with activation in both left and right frontal cortices. An increase of activation in the planum polare bilaterally and in the deep portion of the left frontal operculum was found exclusively when syntactic processes were in focus. Thus, the present data may be taken to suggest an involvement of the left frontal and bilateral temporal cortex when processing syntactic information during comprehension.     

An fMRI investigation of the neural correlates underlying the processing of novel metaphoric expressions

The neural networks associated with processing related pairs of words forming literal, novel, and conventional metaphorical expressions and unrelated pairs of words were studied in a group of 15 normal adults using fMRI. Subjects read the four types of linguistic expressions and decided which relation exists between the two words (metaphoric, literal, or unrelated). According to the Graded Salience Hypothesis (GSH, ), which predicts a selective RH involvement in the processing of novel, nonsalient meanings, it is primarily the degree of meaning salience of a linguistic expression rather than literality or nonliterality, which modulates the degree of left hemisphere (LH) and right hemisphere (RH) processing of metaphors. In the present study, novel metaphorical expressions represented the nonsalient interpretations, whereas conventional metaphors and literal expressions represented the salient interpretations. A direct comparison of the novel metaphors vs. the conventional metaphors revealed significantly stronger activity in right posterior superior temporal sulcus, right inferior frontal gyrus, and left middle frontal gyrus. These results support the GSH and suggest a special role for the RH in processing novel metaphors. Furthermore, the right PSTS may be selectively involved in verbal creativity.     

Semantic facilitation and lexical access during sentence processing: An investigation of individual differences

An earlier experiment (Blank & Foss, 1978) showed that the time required to access the object noun of a sentence was shortened if the noun was preceded by a semantically related verb or adjective. When both the verb and the adjective were semantically related to the noun, the amount of facilitation of lexical access was additive. However, additivity appeared to break down for subjects who did poorly on the comprehension test administered in that experiment, suggesting that the activation function among related lexical items was different for good and poor comprehenders. Such a finding would have implications for theories of lexical facilitation, especially the two-factor theories such as the one proposed by Posner and Snyder (1975). The present experiment again measured access time for the object noun of a sentence when it was preceded by an unrelated or a related verb or adjective (four sentence types). Two groups of college subjects were tested, relatively good (N = 63) and relatively poor (N = 42) comprehenders. The difference in the time taken to retrieve the object noun was ascertained by measuring reaction time to respond to the initial phoneme of the next word in the sentence (phoneme monitoring technique). Reaction times were shorter when the noun was preceded by a semantically related word; the effects of two sources of related context (verb and adjective) appeared to be additive forboth groups of subjects. These results were discussed within the context of two-factor theories of lexical activation and within the context of Morton’s (1969) logogen model.     

An investigation of the interaction between cognitive style and context reinstatement on the memory performance of eyewitnesses

The power of context reinstatement to improve recall is well established, but the degree of effect obtained varies widely between studies. Exploring possible causes for this variation, this paper examines the relationship between cognitive style and the efficacy of context reinstatement in improving free and cued recall in an eyewitness paradigm. Experiment 1, using a live staged event and a 1 week delay, indicated a significant improvement in free recall with the reinstatement of context and, as expected, no such improvement in cued recall. However, analysis of the data according to field dependency, as measured by Witkin, Oltman, Raskin, and Karp's [A manual for the Embedded Figures Test (1971) Palo Alto, CA: Consulting Psychologists Press] Group Embedded Figures Test (GEFT) revealed that, in free recall, field dependent witnesses' scores improved significantly with context reinstatement, whilst the scores of field independent witnesses did not. In cued recall, however, the field independent witnesses scored significantly higher overall than field dependent witnesses. Experiment 2 sought replication of these findings again utilised the GEFT and the Riding [Cognitive Styles analysis (1991) Birmingham: Learning and Training Technology] Cognitive Styles Analysis (CSA). Analysis of the data according to the Wholist-Analytic (W-A) dimension of the CSA, indicated no interaction with either context reinstatement or memorial performance. However the GEFT analysis produced similar results to that obtained in Experiment 1. The meaning of the interaction between the GEFT and both free and cued recall, and the failure of the CSA to similarly interact are discussed, together with the implication of these findings for establishing the value of reinstating context for individual eyewitnesses.     

Implicit processing of emotional words by children with Post-Traumatic Stress Disorder: An fMRI investigation

Background/ObjectiveIn the last decade, socio-political violence in Colombia (South America) has created an environment of extreme/chronic stress. In this study, brain imaging technology (fMRI) and behavioral task performance were used to measure potential deficits in executive functioning for emotional processing in Colombian children.MethodParticipants (22 Post-Traumatic Stress Disorder, PTSD and 22 neurotypical, NT) were asked to perform a word task with implicit emotional salience, which required them to report the color of the ink in which a positive, negative or neutral word was printed.ResultsMixed design analysis of variance showed no group differences in accuracy for determining ink color when presented as a positive or neutral word. However, PTSD children were significantly less accurate (negative words) and notably slower (both positive and negative words) at determining ink color when presented in the context of an emotional word. PTSD processing of positive and negative words was associated with hypoactivation in the superior and middle frontal gyri of the right hemisphere in comparison to NT children.ConclusionsThese results may reflect a deficit in executive functioning for emotionally laden stimuli, perhaps induced as a by-product of their traumatic experiences.     

Decision framing: moderating effects of individual differences and cognitive processing

Two studies examined the effect of an individual difference variable, need for cognition (NC), and processing of the options on the occurrence of risky choice framing effects. In Study 1 (N=206), frame interacted with NC and math skill such that no framing effect was observed among those high in both NC and math skill. No effect was found for the processing manipulation of requesting a reason for one's choices. Study 2 (N=257) enhanced the processing of the problems by asking participants to write out the options as they would describe them to a friend. Results showed that frame interacted with NC and depth of processing such that no framing effect was observed among those high in NC who were in the deep processing condition. These findings suggest that NC and depth of processing need to be considered in concert in order to understand their moderating effects on framing. Copyright © 2004 John Wiley & Sons, Ltd.     

Two facets of cognitive control in analogical mapping: The role of semantic interference resolution andgoal-driven structure selection

The study used scene analogies to investigate two component processes of analogical thinking: resolution of semantic interference, which emerges when the proper mapping between analogically matching objects is incoherent with their categorical features (e.g., stereotypical functions), and goal-driven selection of the key relational structure, by directing attention to the most promising objects which constitute that structure among many other candidate objects. We manipulated interference by placing in corresponding scenes the objects from one category in different relational roles. Selection was loaded by including additional, relationally irrelevant objects in a scene. We also manipulated relational complexity and the presence of salient objects (people) in relations. Increased load on both interference resolution and selection decreased the accuracy of analogical mapping, but these factors did not interact. Moreover, the factors yielded opposite patterns of interaction with relational complexity. Finally, salience eased selection, but tended to negatively influence interference resolution. In summary, inference resolution and selection seem to constitute two relatively independent facets of cognitive control involved in analogical thinking. Selection may act before mapping occurs, while interference influences analogy making only if an interfering object takes part in mapping.     

高功能孤独症者非字面语义理解缺陷：隐喻视角的ERP研究

研究采用事件相关电位技术从隐喻语义理解角度考察了高功能孤独症成人非字面语义理解中的行为特点及脑半球参与模式。行为结果显示：高功能孤独症成人对新异隐喻句的反应时最长,两类隐喻句的反应时均长于普通成人,但错误率上两组被试间无差异。脑电结果显示：高功能孤独症组对新异隐喻句的N400波幅最大,未出现半球偏侧化现象,传统隐喻句在左半球的N400波幅大于右半球,两类隐喻句的N400波幅均大于正常被试。结论：高功能孤独症成人具备隐喻理解能力,并对新异隐喻的理解做出更多努力,但右脑功能异常仍旧存在,左右半球在总体功能或神经联通性上仍旧弱于常人。     

Building theories of reading ability: On the relation between individual differences in cognitive skills and reading comprehension

To date most theories of reading ability have emphasized a single factor as the major source of individual differences in performance. However there has been little agreement on what that factor is. However, candidates have included visual discrimination, phonological and semantic recoding, short-term memory, and utilization of linguistic knowledge and context. The single- factor theories are summarized. Literature is then reviewed to show that no single-factor theory is likely to be right, because a very wide range of component skills and abilities has in fact been shown to correlate with reading success. Among them are discrimination of letter location and letter order during perceptual recognition, use of orthographic regularity as an aid to visual code formation, use of spelling-to-sound regularity in phonological recoding, memory for word order, spontaneous identification of syntactic relations, flexibility in prediction from syntactic and semantic context, and context-specificity in semantic encoding. It is concluded that more complex, multifactor models of reading ability are required, and some recent attempts to collect data conducive to such a model are described. In the process, three different approaches to identifying factors relevant to reading success are delineated. These are general abilities assessment, learning potential assessment, and component skills analysis. Two methods of conducting component skills analysis are presented, and it is recommended that they be used as converging operations. Finally, the results of a component skills analysis are used to construct a tentative example of a class of hierarchical models of reading ability that can be pursued developmentally.     

An event-related potential analysis of extraversion and individual differences in cognitive processing speed and response execution

Individual differences in cognitive processing speed and response execution were examined in relation to extraversion. Event-related potentials (ERPs) were recorded concurrently with reaction time and movement time (MT) measures as participants (N = 67) performed simple reaction time and stimulus-response compatibility tasks. Slower processing speed for extraverts, as indicated by longer latency of a late positive ERP wave, P3, was only evident in conditions in which stimulus information was in conflict with response selection demands. As previously reported, the salient effect in all conditions of both tasks was faster MT for extraverts, an effect that is indicative of differences in fundamental motor processes. On the simple reaction time task, amplitudes of the N1 component, an early negative ERP wave, were smaller for extraverts than for introverts in response to auditory tones, an effect that affirms the enhanced sensory reactivity of introverts to punctate physical stimuli.     

Behavioral and fMRI evidence that cognitive ability modulates the effect of semantic context on speech intelligibility

Text cues facilitate the perception of spoken sentences to which they are semantically related (Zekveld, Rudner, et al., 2011). In this study, semantically related and unrelated cues preceding sentences evoked more activation in middle temporal gyrus (MTG) and inferior frontal gyrus (IFG) than nonword cues, regardless of acoustic quality (speech in noise or speech in quiet). Larger verbal working memory (WM) capacity (reading span) was associated with greater intelligibility benefit obtained from related cues, with less speech-related activation in the left superior temporal gyrus and left anterior IFG, and with more activation in right medial frontal cortex for related versus unrelated cues. Better ability to comprehend masked text was associated with greater ability to disregard unrelated cues, and with more activation in left angular gyrus (AG). We conclude that individual differences in cognitive abilities are related to activation in a speech-sensitive network including left MTG, IFG and AG during cued speech perception.     

The role of performance in the demands and capacities model

The Demands and Capacities Model (DCM) has become an influential framework for considering the factors that are believed to influence the development of stuttering in young children, even though several key aspects of the model have not been fully developed. Siegel (this issue, page 323) raised several valid concerns that must be addressed if the DCM is to achieve its potential for explaining childhood stuttering and suggested that the model would be improved if the elusive concept of capacities were replaced by the more concrete and measurable concept of performance. This paper proposes modifications to the DCM that may help to address several of Siegel's concerns and evaluates the role of performance in understanding the development of childhood stuttering. It is suggested that replacing capacity with performance does not solve the problems identified by Siegel, because implicit assumptions about the child's underlying abilities are still required if the model is to explain a breakdown in speaking performance. To address Siegel's concerns more directly, a different solution is proposed based on reframing the conceptual notions of demands and capacities in terms of measurable aspects of a child's speaking performance and speaking abilities.     

The influence of contextual contrast on syntactic processing: evidence for strong-interaction in sentence comprehension

The present study compares the processing of unambiguous restrictive and non-restrictive relative clauses (RCs) within both a null context and a supportive discourse using a self-paced reading methodology. Individuals read restrictive RCs more slowly than non-restrictive RCs in a null context, but processed restrictive RCs faster than non-restrictive RCs in supportive context, resulting in an interaction between context and RC type. These results provide evidence for two theoretical points. First, principles analogous to those in referential theory [Altmann G. T. M., & Steedman, M. (1988). Interaction with context during human sentence processing. Cognition, 30, 191-238; Crain, S., & Steedman, M. (1985). On not being led up the garden path: The use of context by the psychological parser. In D. Dowty, L. Karttunnen, A. Zwicky (Eds.), Natural language parsing. Cambridge, UK: Cambridge University Press] apply not only in resolving ambiguity but also in processing unambiguous sentences. Second, the discourse context can guide and facilitate interpretive processing. This result suggests that intrasentential factors such as syntax are not autonomous from contextual processing, contrary to the modularity hypothesis [Fodor, J. A. (1983). Modularity of mind. Cambridge, MA: MIT Press].     

Tracking the influence of reflexive attention on sensory and cognitive processing

Previously, we demonstrated that reflexive attention facilitates early visual processing during form discrimination (Hopfinger & Mangun, 1998). In the present study, we tested whether reflexive facilitation of early visual processing will be generated when task load is low (simple luminance detection). Target stimuli that were preceded at short cue-to-target intervals by irrelevant visual events (cues) elicited an enhanced sensory (P1) event-related potential (ERP) component as well as an enhanced longer latency, cognitive ERP component (P300). At long cue-to-target intervals, facilitation in these ERP components was no longer observed, and, although inhibition of return (IOR) was observed in reaction times, the ERPs did not show an inhibition of sensory processing. These results provide converging evidence that reflexive attention transiently facilitates neural processing of visual inputs at multiple stages of analysis (i.e., sensory processing and higher order cognitive processing) but question the view that IOR is manifest at the earliest visual cortical stages of analysis.